Folding blade wind turbine

ABSTRACT

A wind turbine is provided. The turbine includes a support having an axis of rotation, a generator, a plurality of blades rotatably mounted on the support about the axis of rotation, the blades being moveable between a retracted position generally parallel with the axis of rotation and a fully deployed position generally perpendicular with the axis of rotation, the blades being connected to the generator such that rotation of the blades in a direction induced by wind causes the generator to produce electricity, and the provision of electricity to the generator rotates the blades, and a controller connected to the generator and configured to deliver a flow of current to the generator that is sufficient to move the blades from the retracted position toward the fully deployed position and insufficient to move the blades all the way to the fully deployed position. The flow of current induces rotation of the blades in the direction induced by wind, which creates a centrifugal force that moves the blades from the retracted position toward the fully deployed position. As the blades move from the retracted position, the blades have increasing exposure to ambient wind to receive additional rotational force from ambient wind, and the additional rotational force being sufficient to, either alone or in combination with the flow of current, move the blades into the fully deployed position.

CROSS REFERENCE TO RELATED APPLICATIONS

The instant application is a continuation of, and claims priority to,U.S. patent application Ser. No. 16/259,276 entitled FOLDING BLADE WINDTURBINE, filed Jan. 28, 2019, which is a continuation of, and claimspriority to, U.S. patent application Ser. No. 14/558,991 entitledFOLDING BLADE WIND TURBINE, filed Dec. 3, 2014, which claims priority toU.S. Patent Application 61/911,000, filed Dec. 3, 2013, entitled FoldingBlade Wind Turbine. The instant application also relates to U.S. patentapplication Ser. No. 12/461,716 filed Aug. 21, 2009 and Ser. No.12/461,575 filed Aug. 17, 2009. The contents of the foregoingapplications are expressly incorporated herein by reference in theirentireties.

FIELD OF THE INVENTION

Various embodiments described herein relate generally to deployment andretraction of wind turbine blades. More particularly, variousembodiments described herein relate to retraction and deployment of windturbine blades using a combination of electrically induced rotation andwind induced rotation.

BACKGROUND

Modern, wind-driven electricity generators were born in the late 1970's.Until the early 1970s, wind energy filled a small niche market supplyingmechanical power for grinding grain and pumping water, as well aselectricity for rural battery charging. With the exception of batterychargers and rare experiments with larger electricity-producingmachines, the windmills of 1850 and even 1950 differed very little fromthe primitive devices from which they were derived. As of July 2008,wind energy provides approximately 1% of total U.S. electricitygeneration. Smaller designs with as many as 30 blades are common forirrigation in farming.

Most modern wind turbines typically have 3-bladed rotors 10 withdiameters of 10-80 meters mounted atop 60-80 meter towers 12. Theaverage turbine installed in the United States in 2006 can produceapproximately 1.6 megawatts of electrical power. Turbine power output iscontrolled by rotating the blades around their long axis to change theangle of attack (pitch) with respect to the relative wind as the bladesspin around the rotor hub. The turbine is pointed into the wind byrotating the nacelle around the tower (yaw). Turbines are typicallyinstalled in arrays (farms) of 30-150 machines. A pitch controller (forblade pitch) regulates the power output and rotor speed to preventoverloading the structural components—during unusually strong windconditions. Generally, a turbine will start producing power in winds ofabout 5.36 meters/second and reach maximum power output at about12.52-13.41 meters/second (28-30 miles per hour). The turbine will pitchor feather the blades to stop power production and rotation at about22.35 meters/second (50 miles per hour).

Efforts have been made to provide mechanisms to transition the bladesfrom the open deployed position, in which the blades are generallyparallel to the mast and radially about the rotating hub, to the closedretracted position (folded back) in which the blades are generallyperpendicular to the mast in a tight cluster. This allows for reducingthe surface area in high wind environments, as well as for storage andease of transport. U.S. patent application Ser. Nos. 12/461,716 and12/461,575 incorporated herein both disclose designs for opening andclosing the blades.

SUMMARY OF THE INVENTION

According to an embodiment of the invention, a wind turbine is provided.The turbine includes a support having an axis of rotation, a generator,a plurality of blades rotatably mounted on the support about the axis ofrotation, the blades being moveable between a retracted positiongenerally parallel with the axis of rotation and a fully deployedposition generally perpendicular with the axis of rotation, the bladesbeing connected to the generator such that rotation of the blades in adirection induced by wind causes the generator to produce electricity,and the provision of electricity to the generator motor rotates theblades, and a controller connected to the generator and configured todeliver a flow of current to the generator motor that is sufficient torotate the folded blades and move the blades from the retracted positiontoward the fully deployed position and insufficient to move the bladesall the way to the fully deployed position. The flow of current inducesrotation of the blades in the direction induced by wind, which creates acentrifugal force that moves the blades from the retracted positiontoward the fully deployed position. As the blades move from theretracted position, the blades have increasing exposure to ambient windto receive additional rotational force from ambient wind, and theadditional rotational force being sufficient to, either alone or incombination with the flow of current, move the blades into the fullydeployed position.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments in accordance with the present disclosure will bedescribed with reference to the drawings, in which:

FIG. 1 illustrates a side view of an embodiment of the invention in aclosed position.

FIG. 2 illustrates a perspective view of an embodiment of the inventionin a closed position.

FIG. 3 illustrates a side view of an embodiment of the invention in apartially deployed position.

FIG. 4 illustrates a perspective view of an embodiment of the inventionin a partially deployed position.

FIG. 5 illustrates a side view of an embodiment of the invention in anideally fully deployed position.

FIG. 6 illustrates a perspective view of an embodiment of the inventionin an ideally fully deployed position.

FIG. 7 illustrates a block diagram of a controller according to anembodiment of the inventions.

FIG. 8 illustrates a side view of another embodiment of the invention ina closed position.

FIG. 9 illustrates a side view of an embodiment of the invention in apartially deployed position.

FIG. 10 illustrates a side view of an embodiment of the invention in anideally fully deployed position.

DETAILED DESCRIPTION

In the following description, various embodiments will be illustrated byway of example and not by way of limitation in the figures of theaccompanying drawings. References to various embodiments in thisdisclosure are not necessarily to the same embodiment, and suchreferences mean at least one. While specific implementations and otherdetails are discussed, it is to be understood that this is done forillustrative purposes only. A person skilled in the relevant art willrecognize that other components and configurations may be used withoutdeparting from the scope and spirit of the claimed subject matter.

The blade configuration is shown in the attached figures. A generallyvertical mast supports the turbine. Multiple turbine blades arepivotally mounted at their root to a support hub on a nacelle. The pivotallows the blades to move between the fully deployed/open position, andcollapse to a fully closed/retracted position. The blades can also takepartial deployment positions between the deployed and retractedpositions.

The fully deployed position in the figures shows the blades as vertical,although in practice the nature of the embodiment may have some smallangle off vertical on the order 0-15 degrees. In this context, any useof “horizontal” or “vertical” herein is understood to be modified by“generally” to account for such variances from absolute perfection inposition.

The turbine is generally rotatable about the mast to orient into thedirection of the prevalent winds. The turbine referenced herein ispreferably a downwind turbine, in that the blades are oriented towardthe rear of the turbine downwind of the hub and nacelle (relative to thewind).

The support hub is connected to a generator/motor (hereinafter simply“generator”) that is configured to generate electricity, such as apermanent magnet motor. Rotation of the blades causes rotation in thegenerator, which generates electricity in a known manner. Variouselements that interconnect the support hub to the permanent magnet motorare well known in the wind turbine art and are thus not shown herein.

A slideable track ring is located on the shaft rearward of the supporthub. The track ring pivotally supports several connecting rods thatpivotally connect to the blades. The individual connecting rodsmaintains a common angle for the deployment of the individual blades,such that the blades have the same position relative to each otherregardless of deployment position.

When in the fully deployed position, the track ring is in its mostforward position and closest to the support hub. As the blades begin toclose, the track ring will move rearward. The fully closed position willbring the track ring (or some stop connected thereto) proximate to anend or stop on the shaft. Preferably some of the components in the trackring and/or end of the shaft will have magnetic material therein toestablish a weak magnetic lock for the closed position to prevent lowgrade shifting of the components. This can also be achieved with aspring-loaded mechanical sliding or rolling catch device.

A non-limiting example of the above referred to architecture is shown inFIGS. 1-6 . Referring now to FIGS. 1 and 2 , a nacelle 102 is supportedatop a mast 104. Nacelle 102 has a rotating axis that extends toward asupport hub 106. Turbine blades 110 have shafts 108 that are mountedpivotally to support hub 106. In FIGS. 1 and 2 blades 110 are in theretracted position, although they can rotate about the pivot connectionto support hub 106 into other positions as discussed below.

Nacelle 102 includes a generator 112. Generator 112 generateselectricity in response to wind induced rotation of blades 110, which itforwards to downstream equipment shown generically bycontroller/batteries 114 (although the functions of the downstreamequipment is not necessarily limited to a controller and/or batteries).Generator 112 also acts as a motor to drive rotation of blades 110. Theoverall architecture of the interior of nacelle 102 is consistent withknowledge of skill in the art and is not further discussed herein.Generator 112 may include a mechanical brake to slow rotation asdiscussed below.

FIGS. 3 and 4 show the components of FIGS. 1-2 in a partially deployedposition, and reveal the presence of a support rod 116 and a slidingring 118 mounted thereon. The shaft 108 of each blade 110 is pivotallyconnected to sliding ring 118 via brace 120 and pivot points 122. FIGS.5 and 6 show the components of FIGS. 1-2 in an ideally fully deployedposition.

Referring now to FIG. 7 , controller 114 controls the opening, closingand overall position of the blade deployment. The controller may be anysoftware and/or hardware combination to effectuate the control of thetorque forces exerted by the generator 112. To the extent computercontrol is present, then typical computer elements including memory,processor, etc., are present. An energy source via a battery or othersource is provided to support controller 114 and/or provide the currentflow to rotate blades 110. The control commands may be in the form ofsoftware resident on the computer, and as such stored in appropriatecomputer readable media such as hard drive or flash drive. The inventionis not limited to any particular type of computer architecture and/orstorage media, and the components and functionality of FIG. 7 can bebundled or distributed as appropriate.

To open the blades 110 from the retracted position, a reverse current isapplied from batteries or other electrical source to the generator 112;preferably this current is applied gradually from zero to apredetermined value, although this need not be the case, and if gradualit need not be linear. The electrical input causes the generator 112 toact as a rotating motor to spin the entire assembly of blades 110 in thesame direction as the wind would induce.

This spinning motion causes the blades 110 to move outward from theirtips through the effect of the centrifugal force imparted by thespinning action. The blades 110 will thus move to a transitionalintermediate position between the retracted and fully deployed position.This transition is shown generally by comparing FIGS. 1 and 3 and 2 and4 , respectively. FIGS. 3 and 4 show a generally 45 degree angle for thetransitional intermediate position, but this is for illustrationpurposes only and does not limit the state of deployment of the blades110 based on current flow.

As the blades 110 move outward from the retracted position, the surfacearea of the blades 110 relative to the wind increases. Since the blades110 are designed to rotate about the axis in the presence of wind,incoming ambient wind will begin to exert a rotation force on the blades110 as the wind moves over the blades 110; this rotational forceincreases as the blades 110 further deploy. While initially theinfluence of wind is negligible due to the small angle of deployment, atsufficient deployment angle the interaction of the wind will cause theblades 110 to rotate faster than the speed induced by the current. Thisincrease in speed further enhances the centrifugal force effect tofurther deploy the blades 110 toward the fully deployed position inFIGS. 5 and 6 . The wind will also physically bias the blades 110 backtoward the retracted position, but in normal operation the openingeffect of the centrifugal force is stronger than the closing effect ofthe direct wind; the collective forces from the wind net results infurther deployment of the blades 110 to toward the fully deployedposition.

This cycle continues with the blades 110 continuing to deploy, theincrease in surface area during deployment captures more wind, theincrease in wind capture further increases the rotational speed, theincrease in rotational speed increase increases the centrifugal force,which causes further deployment. The cycle continues until the speed andcentrifugal force reach a point that the blades 110 move into the fullydeployed position.

In the initial transition from the retracted position to fully openposition, the surface area of blades 110 presented to the wind isinsufficient to induce sufficient rotation from the wind alone to deploythe blades 110. If the applied reverse current were removed or reducedin this initial phase, the blades 110 would either remain in theircurrent state of deployment or retract back to the retracted position.

The deployment methodology above only requires enough reverse currentfor sufficient deployment of the blades 110 to reach a transition pointin which the wind can on its own induce sufficient rotation in theblades 110 to continue the deployment process without contribution fromthe current flow. The system parameters consistent with this transitionevent may be a percentage of the maximum rotational speed, electricaloutput of the turbine, and/or deployed angle; other appropriate systemparameters could also be used. Once this transition point is reached (ora point slightly beyond, as may be measured by a predetermined voltage,speed, percentage or the like), controller 114 begins to taper theapplication of reverse current back to zero while the force of the windapplies the necessary energy to continue the deployment. If for somereason the speed drops off (e.g., a drop in wind speed) before fulldeployment, the reverse current can be reengaged to reinitiate thedeployment process. In the alternative, current can continue beingapplied during the entire deployment cycle.

The control methodology above thus initially relies upon rotationinduced by reverse current to partially deploy the blades 110. Thisreverse current is preferably not sufficient to induce full deployment,such that without wind contribution the blades 110 will not reach thefully deployed position. Once the transition point is reached, thereverse current can be drawn down and generator 112 slowly begins to actas an electrical generator rather than a motor while the wind takes overdeployment. If for any reason there is a backslide (e.g., a sudden dropin wind), then control can increase the reverse current to bring thegenerator 112 back to the preferred state for deployment.

Once the blades 110 reach the fully deployed position, they will tend toremain deployed absent controlled retraction. This is because thecentrifugal force caused by rotation overcomes the tendency of the windto force the blades 110 rearward. This balance maintains deploymentregardless of wind speed within normal operating ranges.

As generator 112 extracts power from the rotational forces imparted bythe wind turbine blades 110, they create a torque drag that allows thewind to push the blades 110 rearwards slightly from their fully deployedposition into a slight coning configuration, which can be somewhatbeneficial for the directional control of the turbine into the wind (andalso to induce coning or partially open position to mitigate the effectof damaging winds and still allow partial operation). There is a balancepoint between the torque forces imparted by the generator 112 slowingrotation and the rearward forces of wind pressure on the blades 110causing them to be pushed rearward into a partially deployed or conedposition. In other words, as the blades 110 speed up the generator 112automatically through its basic nature imparts additional torque forcesthus slowing the rotation of blades 110 slightly maintaining a partiallydeployed or coned position. And reversely as the wind speed slowsslightly the rearward forces imparted by the wind on the blades 110diminishes also allowing them to open more towards their verticaloperating position. This activity can automatically create a desirablebalance point for safe coned operation in strong potentially damagingwinds. The controller 114 can also be utilized to augment this naturallyoccurring condition. This may account for some deviation in the fullydeployed position from a perfect vertical, and this is referred toherein as generally vertical or generally perpendicular to the axis ofrotation of the turbine.

It may on occasion be desirable to move the deployed blades 110 out ofthe fully deployed position into a partially deployed position or theretracted position. For example, winds may reach a point that they placeundue stress on the system in full deployment. A partial retraction ofthe blades 110 will reduce the effect of the wind on the blades 110, andthus the overall stress of the system. This can be done by adding torquefrom the generator and/or a mechanical brake. In another example, thewinds may reach a critical point that the blades 110 need to be closedfor necessity. In yet another example, the blades 110 may need to beclosed to effectuate relocation of the turbine or maintenance.

The methodology for moving the blades 110 from the fully deployedposition to a partially deployed position or a retracted positiondepends on the presence of sufficient wind.

In the presence of sufficient wind, the blades 110 are typically intheir fully deployed position and will remain so because the rotationinduces a centrifugal force in favor of deployment that is stronger thanthe rearward wind pressure on the blades 110 in favor of retraction.This balance can be changed by applying a controlled brake viacontroller 114 to the rotation of the blades 110 induced by, e.g., thegenerator 112 adding excess torque or a failsafe mechanical brake.Slowing the rotation of blades 110 decreases the centrifugal forcesholding the blades 110 in the fully deployed position. When thedeployment influence of the centrifugal force falls below the directreward pressure of the wind on the blades, the wind flow will begin tomove blades 110 out of the fully deployed position.

As the blades 110 move out of the fully deployed position, the ambientwind provides less and less rotational force. If that imposed forcedrops below the decreased centrifugal force, a balance point is reachedand defines a partially deployed position in which the blades 110 willsettle and continue to rotate. However, if the centrifugal force isinsufficient to maintain the blades 110 in any deployed position, theywill move all of the way to the retracted position.

Braking can be initiated by a mechanical brake operating per thecontroller 114. In addition and/or the alternative, permanent magnetgenerators can act as brakes if the controllers causes the generators toextract significantly more electrical energy than they normally woulduse during normal operation. When this occurs, a braking action isapplied to the rotating shaft and blade assembly by the generator 112.

Applied braking is preferably controlled to move the blades 110 asdesired. For full closure, the blades 110 would simply be allowed tomove, although preferably the constraint on rotation would only besufficient to allow a slow transition (rather than an uncontrolledmotion that could damage the architecture).

For partial closure, the application of the brake would be sufficient toreach the desired angle of deployment, and then regulated to keep theblades 110 in that position. In the alternative, one or more selectivelyphysical stops or locks may be used to maintain a desired angle in sucha case the brake can be released, but the stop physically preventsfurther deployment beyond the desired angle. Wind speed, rotation speedand/or other system sensors may be provided to monitor the state ofdeployment that allows the controller to react to the same. Angles ofupwards of about 45 degree retraction may be possible, although theinvention is not so limited.

In the absence of sufficient wind, the above retraction methodology willnot be effective because there is insufficient wind force to induce therearward motion of the blades 110. In these circumstances—in which theblades 110 will be either still or in light rotation—control applies areverse current to the generator 112 to rotate the blades 110 indirection opposite to what the wind would normally induce. This createsa reverse force on the blades 110 that urges them toward the retractedposition, and they will so move.

FIGS. 8-10 show another embodiment of the invention, in which likenumerals represent like elements. This embodiment shows that nacelle 102can be omitted in favor of support components. A stop 124 can also beprovided on rod 116 to prevent further movement of sliding ring 118.Stop 124 may also include a locking component such as described hereinto hold the blades 110 in the retracted position.

Computing elements described herein can be performed in other generalpurpose or specialized computing devices, such as personal computers,desktop or laptop computers, or mainframe computers, as well ascellular, wireless, and handheld devices running mobile software andcapable of supporting a number of networking and messaging protocols.There may any number of workstations running any of a variety ofcommercially-available operating systems and other known applications.These devices also can include other electronic devices, such as dummyterminals, thin-clients, gaming systems, and other devices capable ofcommunicating via a network.

Most embodiments utilize at least one network that would be familiar tothose skilled in the art for supporting communications using any of avariety of commercially-available protocols, such as TCP/IP, FTP, SFTP,UPnP, NFS and CIFS. The network can be, for example, a local areanetwork, a wide-area network, a virtual private network, the Internet,an intranet, an extranet, a public switched telephone network, aninfrared network, a wireless network, and any combination thereof.

In embodiments where the computing device includes a server, the servercan run any of a variety of server or mid-tier applications, includingHTTP servers, FTP servers, CGI servers, data servers, Java servers, andbusiness application servers. The server(s) also may be capable ofexecuting programs or scripts in response to requests from user devices,such as by executing one or more Web applications that may beimplemented as one or more scripts or programs written in anyprogramming language, such as Java®, C, C# or C++, or any scriptinglanguage, such as Perl, Python, or TCL, as well as combinations thereof.The server(s) may also include database servers, including withoutlimitation those commercially available from Oracle®, Microsoft®,Sybase®, and IBM®.

The environment can include a variety of data stores and other memoryand storage media as discussed above. These can reside in a variety oflocations, such as on a storage medium local to (and/or resident in) oneor more of the computers or remote from any or all of the computersacross the network. In a particular set of embodiments, the informationmay reside in a storage-area network (“SAN”) familiar to those skilledin the art. Similarly, any necessary files for performing the functionsattributed to the computers, servers, or other network devices may bestored locally and/or remotely, as appropriate. Where a system includescomputerized devices, each such device can include hardware elementsthat may be electrically coupled via a bus, the elements including, forexample, at least one central processing unit (CPU), at least one inputdevice (e.g., a mouse, keyboard, controller, touch screen, or keypad),and at least one output device (e.g., a display device, printer, orspeaker). Such a system may also include one or more storage devices,such as disk drives, optical storage devices, and solid-state storagedevices such as random access memory (“RAM”) or read-only memory(“ROM”), as well as removable media devices, memory cards, flash cards,etc.

Such devices also can include a computer-readable storage media reader,a communications device (e.g., a modem, a network card (wireless orwired), an infrared communication device, etc.), and working memory asdescribed above. The computer-readable storage media reader can beconnected with, or configured to receive, a computer-readable storagemedium, representing remote, local, fixed, and/or removable storagedevices as well as storage media for temporarily and/or more permanentlycontaining, storing, transmitting, and retrieving computer-readableinformation. The system and various devices also typically will includea number of software applications, modules, services, or other elementslocated within at least one working memory device, including anoperating system and application programs, such as a client applicationor Web browser. It should be appreciated that alternate embodiments mayhave numerous variations from that described above. For example,customized hardware might also be used and/or particular elements mightbe implemented in hardware, software (including portable software, suchas applets), or both. Further, connection to other computing devicessuch as network input/output devices may be employed.

Storage media and computer readable media for containing code, orportions of code, can include any appropriate media known or used in theart, including storage media and communication media, such as but notlimited to volatile and non-volatile, removable and non-removable mediaimplemented in any method or technology for storage and/or transmissionof information such as computer readable instructions, data structures,program modules, or other data, including RAM, ROM, EEPROM, flash memoryor other memory technology, CD-ROM, digital versatile disk (DVD) orother optical storage, magnetic cassettes, magnetic tape, magnetic diskstorage or other magnetic storage devices, or any other medium which canbe used to store the desired information and which can be accessed by asystem device. Based on the disclosure and teachings provided herein, aperson of ordinary skill in the art will appreciate other ways and/ormethods to implement the various embodiments.

The specification and drawings are, accordingly, to be regarded in anillustrative rather than a restrictive sense. It will, however, beevident that various modifications and changes may be made thereuntowithout departing from the broader spirit and scope of the invention asset forth in the claims.

What is claimed is:
 1. A wind turbine, comprising: a support having anaxis of rotation; a generator; a plurality of blades rotatably mountedon the support about the axis of rotation, the blades being moveablebetween a retracted position generally parallel with the axis ofrotation and a fully deployed position generally perpendicular with theaxis of rotation; the blades being connected to the generator such thatrotation of the blades in a direction induced by wind causes thegenerator to produce electricity, and provision of electricity to thegenerator rotates the blades; a controller connected to the generator;the turbine being configured to execute first and second retractionprotocols to move the blades from the fully deployed position to theretracted position: the first retraction protocol comprising slowingrotation of the blades, such that due to reduction in centrifugal forcethe blades begin to transition to the retracted position as rotationslows; and the second retraction protocol comprising rotating the bladesin an opposite direction to that induced by ambient wind.
 2. The turbineof claim 1, further comprising: the first and second retractionprotocols are stored in a memory; and the turbine being configured toexecute the first and second retraction protocols comprises thecontroller being configured to (a) select the first or second retractionprotocol, and (b) implement the selection.
 3. The turbine of claim 2,wherein the controller: selects the first retraction protocol when theturbine is rotating in ambient wind; and selects the second retractionprotocol when the turbine in not rotating in ambient wind.
 4. Theturbine of claim 1, wherein the first retraction protocol is executed byapplying a brake to the blades, increasing current draw on thegenerator, or applying reverse current flow to the generator.
 5. Amethod for moving blades of a wind turbine, comprising: providing thewind turbine, the wind turbine comprising: a support having an axis ofrotation; a generator; a plurality of blades rotatably mounted on thesupport about the axis of rotation, the blades being moveable between aretracted position generally parallel with the axis of rotation and afully deployed position generally perpendicular with the axis ofrotation; the blades being connected to the generator such that rotationof the blades in a direction induced by wind causes the generator toproduce electricity, and the provision of electricity to the generatorrotates the blades; executing a first or a second retraction protocol tomove the blades from the fully deployed position to the retractedposition: the first retraction protocol comprising slowing rotation ofthe blades, such that due to reduction in centrifugal force the bladesbegin to transition to the retracted position as rotation slows; and thesecond retraction protocol comprising rotating the blades in an oppositedirection to that induced by ambient wind.
 6. The method of claim 5,further comprising: selecting the first retraction protocol for theexecuting when the turbine is rotating in ambient wind; and selectingthe second retraction protocol for the executing when the turbine in notrotating in ambient wind.
 7. The method of claim 5, wherein executingthe first retraction protocol comprises applying a brake to the blades,increasing current draw on the generator, or applying reverse currentflow to the generator.
 8. The method of claim 5, further comprising: thewind turbine includes the first and second retraction protocols storedin a memory; and the executing comprises: selecting the first or secondretraction protocol from the memory; and implementing the selection. 9.A wind turbine, comprising: a support having an axis of rotation; agenerator; a plurality of blades rotatably mounted on the support aboutthe axis of rotation, the blades being moveable between a retractedposition generally parallel with the axis of rotation and a fullydeployed position generally perpendicular with the axis of rotation; theblades being connected to the generator such that rotation of the bladesin a direction induced by wind causes the generator to produceelectricity, and provision of electricity to the generator rotates theblades; a controller connected to the generator; and the turbine beingconfigured to execute at least a first retraction protocol to move theblades from the fully deployed position to the retracted position, thefirst retraction protocol comprising rotating the blades in an oppositedirection to that induced by ambient wind.
 10. The turbine of claim 9,further comprising: the at least a first retraction protocol is storedin a non-transitory computer readable memory.